Cam for stamp-batteries.



A. B. FOOTE.

CAM FOR STAMP BATTERIES.

APPLICATION FILED SEPT. 15, 1914.

1 1 52, 1 6 1 Patented Aug. 31, 1915.

INVENTOR J6 Mn \V [TN ESSES:

COLUMBIA PLANonnAm-l co., WASHINGTON, n. c.

ARTHUR B. FOOTE, 0F GRASS VALLEY, CALIFORNIA.

cAivr non STAMP-BATTERIES.

Specification of Letters Patent.

rammed Aug. 31, 1915.

Applicationfiled September 15, 1914. SeriaI No. 861,878

To all "whom it may concern:

Be it known that I, ARTHUR B. Foo'rn,

a citizen of the United States, residing at without shock from a state of rest and to im-- part to the stem a constantly accelerating velocity and momentum to carry it to a height suflicient to produce a resultant drop of predetermined length.

Another object of the invention is to so design the cam that the life of the battery elements is greatly conserved by materially reducing vibrations, and which operates upon the parts in such a manner that the slipping of tappets and separation of shoes from the stems is eliminated, thus saving a great deal of valuable operating time and costly labor.

A. further object is to provide a cam of such contour that the speed of revolution of the cam shaft may be considerably increased with a resultant increase in the number of drops of stamp per minute and without the serious deterioration of parts commonly incident to battery parts as now generally in use when speed is increased.

The invention consists of the parts and the combination and construction of parts I as hereinafter more fully described and claimed, having reference to the accompanying drawings, in which Figure l is a side elevation of a battery stem with a tappet, and a cam on the shaft. Fig. 2 is a view of the cam and its development.

At 2 is shown a cam shaft perpendicular to which stands a battery stem 3 with a tappet 4 suitably secured thereon. On the cam shaft is secured a cam 5 to which this invention particularly relates.

Battery cams are usually provlded wlth diametrically opposite active surfaces 6 coactive successively with the lower end of the tappet 4:, so that during one revolution of the shaft the stem is lifted and dropped twice. Ordinarily the speed of batteries is 95 drops per stem per minute; this being the most economical for wear of parts. My present cam is expressly designed so that the speed of operation may be economically and safely increased to 110 drops per minute, and to greatly eliminate vibration and lessen the noise of cam impact. All this is at once accomplished by giving the active cam surfaces 6 such a form that the cam engages the stem tappet quietly and gradually and subsequently acts to lift the stem with its shoe with a constantly accelerating velocity and momentum. To that end the effective camsurface 6 is laid off with an elevational curvature of suitable angular length about the center of the cam and with a peripheral addendum which constantly increases in height between each degree of the included angle between the root of the curve or cam surface and its apex. This is shown embodied in one form in the diagram where the included angle of the cam surface is 90. By dividing this into parts of 10 each and projecting radii threat the desired curve is readily laid off by marking the radii commencing with the root point 8 and each succeeding one at a point a greater distance from the cam center, as at a, b, c, d, e, f, g, [1. and 2'. A constantly accelerated lifting action is had when the radial distance between each of these arbitrary points a, 6 etc, varies increasingly.

I have made and successfully utilized in stamp milling a cam in which the effective curve surfaces are developed as in Fig. 2, in which the addendum, in an arc of 90, is obtained by pointing of the radii by the concentric arcs a, Z), c, d, e, f, g, h, and 2'; these arcs being struck from a radius s and projected from intersections therewith of sines projected from a quarter circle a, the radius of which equals the desired height of addendum curve of the cam. The spacing along the projected radius 8 represents distances traversed by the stem in equal intervals of time during a quarter revolution of the cam shaft. This graphically illus' trates but one form of curve for a cam de signed to lift a stem at a predetermined varying rate of speed. The momentum given the stem will cause it to continue upward movement after leaving the apex of the cam, so that the length of drop will exceed the actual cam lift.

7 Having thusgdesciibed my inventien What I claini and desire to secure" by Lettei'sPat ent is 'nating in a free apex permitting the ta pets 10' to be disengaged from said" surface, where- 33 by themomcntun giyen the stern willcause it to continue upward" movement after leavingthe-apex' so that the length ofthe tappet drop will exceed the actual cam lift.

In testimony,whereofilhave hereunto set 15 my hand in the presence of two subscribing Witnesses.-

H ARTHUR B. FOOTE. c

Witnesses; V

' W. HEAnnY,

M. EWING.

(Topics this pal tentginay'be obtained fb'r' five cents 6301i, addrssing't'l're Commissioner ofiatEn-ts, 

